RE: [PATCH net-next v4 2/2] net: phy: Add support for PHY timing-role configuration via device tree

[Divya.Koppera]

Hi @Oleksij Rempel

> -----Original Message-----
> From: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
> Sent: Tuesday, October 1, 2024 1:07 PM
> To: Andrew Lunn <andrew@xxxxxxx>; Heiner Kallweit
> <hkallweit1@xxxxxxxxx>; David S. Miller <davem@xxxxxxxxxxxxx>; Eric
> Dumazet <edumazet@xxxxxxxxxx>; Jakub Kicinski <kuba@xxxxxxxxxx>; Paolo
> Abeni <pabeni@xxxxxxxxxx>; Rob Herring <robh@xxxxxxxxxx>; Krzysztof
> Kozlowski <krzk+dt@xxxxxxxxxx>; Conor Dooley <conor+dt@xxxxxxxxxx>;
> Florian Fainelli <f.fainelli@xxxxxxxxx>
> Cc: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>; Russell King
> <rmk+kernel@xxxxxxxxxxxxxxx>; kernel@xxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; Russell King
> <linux@xxxxxxxxxxxxxxx>; devicetree@xxxxxxxxxxxxxxx
> Subject: [PATCH net-next v4 2/2] net: phy: Add support for PHY timing-role
> configuration via device tree
> 
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the
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> 
> Introduce support for configuring the master/slave role of PHYs based on the
> `timing-role` property in the device tree. While this functionality is necessary
> for Single Pair Ethernet (SPE) PHYs (1000/100/10Base-T1) where hardware
> strap pins may be unavailable or incorrectly set, it works for any PHY type.
> 
> Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
> Reviewed-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>
> ---
> changes v4:
> - add "Reviewed-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>"
> changes v3:
> - rename master-slave to timing-role
> ---
>  drivers/net/phy/phy-core.c   | 33 +++++++++++++++++++++++++++++++++
>  drivers/net/phy/phy_device.c |  3 +++
>  include/linux/phy.h          |  1 +
>  3 files changed, 37 insertions(+)
> 
> diff --git a/drivers/net/phy/phy-core.c b/drivers/net/phy/phy-core.c index
> 1f98b6a96c153..97ff10e226180 100644
> --- a/drivers/net/phy/phy-core.c
> +++ b/drivers/net/phy/phy-core.c
> @@ -412,6 +412,39 @@ void of_set_phy_eee_broken(struct phy_device
> *phydev)
>         phydev->eee_broken_modes = broken;  }
> 
> +/**
> + * of_set_phy_timing_role - Set the master/slave mode of the PHY
> + *
> + * @phydev: The phy_device struct
> + *
> + * Set master/slave configuration of the PHY based on the device tree.
> + */
> +void of_set_phy_timing_role(struct phy_device *phydev) {
> +       struct device_node *node = phydev->mdio.dev.of_node;
> +       const char *master;
> +
> +       if (!IS_ENABLED(CONFIG_OF_MDIO))
> +               return;
> +
> +       if (!node)
> +               return;
> +
> +       if (of_property_read_string(node, "timing-role", &master))
> +               return;
> +
> +       if (strcmp(master, "force-master") == 0)
> +               phydev->master_slave_set = MASTER_SLAVE_CFG_MASTER_FORCE;
> +       else if (strcmp(master, "force-slave") == 0)
> +               phydev->master_slave_set = MASTER_SLAVE_CFG_SLAVE_FORCE;
> +       else if (strcmp(master, "prefer-master") == 0)
> +               phydev->master_slave_set =
> MASTER_SLAVE_CFG_MASTER_PREFERRED;
> +       else if (strcmp(master, "prefer-slave") == 0)

I would suggest to use "preferred" instead of "prefer" to be in sync with existing macros.

> +               phydev->master_slave_set =
> MASTER_SLAVE_CFG_SLAVE_PREFERRED;
> +       else
> +               phydev_warn(phydev, "Unknown master-slave mode %s\n",
> +master); }
> +
>  /**
>   * phy_resolve_aneg_pause - Determine pause autoneg results
>   *
> diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
> index 560e338b307a4..4ccf504a8b2c2 100644
> --- a/drivers/net/phy/phy_device.c
> +++ b/drivers/net/phy/phy_device.c
> @@ -3608,6 +3608,9 @@ static int phy_probe(struct device *dev)
>          */
>         of_set_phy_eee_broken(phydev);
> 
> +       /* Get master/slave strap overrides */
> +       of_set_phy_timing_role(phydev);
> +
>         /* The Pause Frame bits indicate that the PHY can support passing
>          * pause frames. During autonegotiation, the PHYs will determine if
>          * they should allow pause frames to pass.  The MAC driver should then
> diff --git a/include/linux/phy.h b/include/linux/phy.h index
> a98bc91a0cde9..ff762a3d8270a 100644
> --- a/include/linux/phy.h
> +++ b/include/linux/phy.h
> @@ -1260,6 +1260,7 @@ size_t phy_speeds(unsigned int *speeds, size_t size,
>                   unsigned long *mask);
>  void of_set_phy_supported(struct phy_device *phydev);  void
> of_set_phy_eee_broken(struct phy_device *phydev);
> +void of_set_phy_timing_role(struct phy_device *phydev);
>  int phy_speed_down_core(struct phy_device *phydev);
> 
>  /**
> --
> 2.39.5
> 

LGTM.

Reviewed-by: Divya Koppera <divya.koppera@xxxxxxxxxxxxx>